Dishwashing apparatus



Feb. 13, 1968 I J, MlXON 3,368,573 DISK-{WASHING APPARATUS Filed Oct. 7,1965 WITNESSES Q INVENTOR Joseph L.. Mixon a BY Y a, ATTORNEYQL? UnitedStates Taten't C 3,368,573 DISHWASHING APPARATUS Joseph L. Mixon,Galesburg, Ill., assignor to Westinghouse Electric Corporation,Pittsburgh, Pa., a corporation of Pennsylvania Filed Oct. 7, 1965, Ser.No. 493,820 7 Claims. (Cl. 134176) ABSTRACT OF THE DISCLOSURE Apparatusfor dispersing a stream of water in a pattern over the upper rack of adishwasher by means of a rotatable wheel having a hub, spokes, and anouter ring, the hub having one open part through which a part of thewater passes directly upwardly for producing an inner pattern, the ringhaving inner and outer inclined surfaces for deflecting additional waterinto intermediate and outer patterns, respective-1y.

This invention relates to dishwashing apparatus generally and inparticular to water dispersing apparatus for ensuring water coverage ofthe upper portion of the washing chamber.

Current domestic dishwashers are typically provided with an openworkrack in the lower portion of the washing chamber and another openworkrack in the upper part of the washing chamber for supporting articles tobe washed. A primary water distributor, usually in the form of arotatable arm, is located below the lower rack and fed with Washing andrinsing water which is discharged in spray form through a multitude ofopenings upon the upper surface of the arm. The discharge of the waterdrives the arm in its rotating path in a reaction manner. Supplementarywater distributing means is also provided in many models fordistributing water upwardly to the upper rack from an intermediatelocation. This invention is principally directed to supplementary waterdispersing means and has as its objection the provision of a relativelyinexpensive but highly effective device for producing desired spraypatterns in the upper portion of the dishwasher.

Briefly, in accordance with the invention, a rotatable water dispersingwheel is provided in the central part of the dishwasher at a level abovethe lower spray arm. It is located to receive a stream ofupwardly-directed water issuing from the central part of the lower sprayarm. The heart of the invention may be considered to reside in thestructural arrangement of the Wheel which includes a central hub, anouter ring, and a series of spokes radiating from the hub to the ring.The ring has inclined surface portions on both its inner and outercircumferential faces to disperse a part of the stream into twoconstant, generally cone-shaped water patterns which overlap in theupper part of the chamber. The hub includes a cut-out segment permittingthe passage of part of the stream directly upwardly in the form of atriangular pattern which sweeps around the central area of the upperportion of the dishwasher to fill out the coverage. The spokes serve asimpulse surfaces which cause the wheel to rotate as a result of thewater stream impulse.

The invention will be described in connection with the accompanyingdrawing illustrating several preferred embodiments by way of example,and wherein:

FIGURE 1 is a fragmentary, partly-broken side view of dishwasherapparatus embodying the invention;

FIG. 2. is a fragmentary, partly-broken and partlysectioned elevationalview of the dispersal apparatus and underlying rotating arm;

FIG. 3 is a top view of the dispersal wheel; and

3,368,573 Patented Feb. 13, 1968 FIG. 4 is a fragmentary, sectional,partly-schematic view of the dispersal wheel illustrating the patternsof water to be derived from the wheel in operation, and indicating thepaths which the water follows in achieving these patterns.

The dishwasher illustrated has the conventional, generally-rectangular,box shape encompassing the washing chamber 10 which has a sump 12 formedin its bottom wall, a rotatable spray arm 14 immediately above the sump,a lower dish rack 16, and an upper dish rack 18. The dishwasher shown isof the front-loading type in which a front door 20 is dropped and boththe bottom rack 16 and top rack 18 are adapted to be pulled horizontallyforward out of the washing chamber on suitable track means so that thearticles to be washed may be loaded in the racks.

A pump and motor assembly 22 are provided below the bottom wall fordelivering water under pressure into the interior of the rotatable sprayarm 14. As is conventional, the water issuing under pressure from thetop surface of the spray arm 14 through tangentially-directed outletswill cause the spray arm 14 to rotate and the water issuing from thisrotating arm is flung upwardly and outwardly through the lower rack 16and to a lesser extent about the upper portion of the washing chamber10.

The dispersal apparatus according to this invention for supplementingthe distribution of water about the upper portion of the water washingchamber 10 may conveniently be mounted upon the movable lower rack 16for movement therewith since the supplementary dispersal assembly islightweight, relatively small, and does not need to be directlyconnected to a source of water from the lower spray arm 14.

As shown in FIG. 2, the rotatable lower spray arm 14 is provided withthe reaction and spray outlets 26 on the upper surface of the arm, andis provided with an upwardly-directed, central, jet outlet 28 throughwhich a portion of the water delivered to the spray arm 14 is deliveredupwardly in the form of a substantially solid stream. The lower rack 16is located immediately above the spray arm and supports a hollow,truncated, right cone 30' having its axis aligned vertically with thevertical axis of the jet outlet 28. The upper end of the cone 30 isprovided with a spider-like arrangement 32 for supporting a central core34 to which the dispersal wheel is secured by means of a screw 36 whichpasses freely down through a bore in the shank 38 of the wheel. Thestream of water is directed up through the hollow cone to the wheel.

Referring now to FIGS. 2 and 3, the wheel includes a central hub 40, anouter ring 42, and a series of radiating spokes 44 securing the ring tothe hub. As shown in FIG. 3, a portion of the hub between two adjacentspokes 44 is omitted so that an open pie-shaped segment 46 is formed.

Since the structural configuration of the wheel is of importance inobtaining the water distribution patterns desired and available inaccordance with the invention, attention will now be directed to theshape and locational relationships of the parts involved. As may be bestseen in FIGS. 2 and 4, the outer ring 42 includes an outercircumferential surface portion 48 which is inclined outwardly ordiverges in a bottom-to-top direction. The inner periphery of the ring42 is provided with a circumferential surface portion 50 which issimilarly inclined. The lower surface 52 of the hub is essentially flat,except for the inward continuation of the spokes 44 in the presentlypreferred commercial form of the device, and lies in a horizontal planeintersecting the inner inclined portion 50 of the ring.

The general water distribution patterns obtained from the dispersalwheel described is illustrated in FIG. 4 in which arrows are used toshow the general direction of water passing upwardly to and through thewheel. It is here emphasized that the illustrated patterns areessentially diagrammatic in the sense they are intended to portray thesubstance of the patterns rather than sharply defining the absoluteborders of the patterns. However, three generally perceptible patternsare obtained from the dispersal apparatus of the invention.

The inner portion designated 54 is obtained from water passing throughthe open segment 46 formed by the pieshaped slot in the hub and definedat its outer radial limit by the inner face of the ring 42. This pattern54 is somewhat triangular in horizontal section and is slightlydiverging in elevation. It moves in a path around the vertical axis ofthe spinner wheel. The pattern is by design progressively heavier towardthe radially outer part of the segment opening 46 so that the waterdelivered is generally proportional to the area to be covered. However,some of the water is deflected back in toward the center by the innersurface of the outer ring 42 as indicated by the arrow 56. As noted,this inner pattern sweeps the center part of the upper rack 18 as thewheel rotates, and for a conventional size domestic dishwasherapproximately twenty-four inches square in plan in its interior,preferably has an outer diameter of about ten inches at the bottom ofthe upper dish rack.

The intermediate water pattern is indicated by the numeral 58 in FIG. 4,and is derived partly from water which passes directly upwardly throughthe open annulus between adjacent spokes 44, and partly from deflectedwater. The deflected water is that part which first strikes the flatunderside hub surface 52 and is directed generally outwardly against theinclined surface 50 of the outer ring 42 so that it is deflectedupwardly in the pattern shown. In plan the pattern is ring-shaped, andin elevation generally conical. It is a constant pattern having an innerdiameter at the upper rack bottom of about eight inches and overlaps theouter border of the inner pattern 54. The outer diameter at that levelis about eighteen inches.

The third and outer pattern 62 is derived from water passing upwardlyoutside of the outer ring 42 and in part being deflected by the inclinedouter surface 48 of the ring. This outer pattern is also ring-shaped inplan and generally conical in elevation. Its inner peripheral border atthe upper rack level overlaps the outer peripheral border of the secondpattern 58. The inner diameter there is about sixteen inches, and theouter diameter is limited by the tub to about twenty-four inches.

It is noted that it is the part of the stream of water which strikes thespokes 44 which causes the wheel to rotate. In the presently preferredcommercial embodiment of the invention, the bottom edges of the spokes44 are simply rounded, and the side surfaces of the spokes need not beprovided with any tilt or inclination. However, in the commercial deviceincorporating the described dispersal device, the water supplied to thejet outlet 28 of the rotating spray arm is swirling to a degree due tothe volute of the centrifugal pump used. Accordingly, suflicientoppositely-directed forces are exerted upon spokes at opposite sides ofthe wheel to cause the wheel to spin at a rate of 15 to 30 rpm. in thecommercial device. Of course, with a stream wherein such forces are notavailable, the spokes may be slightly tilted to get the desired wheelrotation. In any case, however, the wheel is designed to operate as animpulse type wheel, as distinguished from a reaction type Wheel.

It is not necessary that the stream be confined within the core 30 inits passage to the wheel, but the core does perform a support functionand also presents obstructions from being placed in the path of thestream. The wheel may in some instances preferably be supported directlyon the lower rack and the core 30 omitted.

As one example of dimensions for a satisfactory wheel for domesticdishwashers, the outer diameter of the ring 42 is about 2 /8 inches, theouter diameter of the hub 40 is about 1 1 inches, and the inner diameterof the outer ring 42 is about 1 inches. Both the inner and outer taperedsurfaces of the outer ring 42 are tapered at about 45. The level of theflat undersurface of the hub 40 is about of an inch above the lower edgeof the inner tapered surface 50. The wheel is mounted about 8 to 9inches above the outlet of the rotating lower spray arm. The outlet 28of the arm is sized relative to the spray outlets 26 on the uppersurface of the spray arm so that approximately one-half to two-thirds ofthe water is delivered out of the stream outlet while the remainder isdelivered as a spray.

The dimensions and relationships expressed give one example of a devicewhich operates satisfactorily, and accordingly are only to be taken asexemplary, and is in no way limiting.

I claim as my invention:

1. Dishwashing apparatus comprising:

an enclosed washing chamber;

an upper and a lower openwork rack in said chamber for supportingarticles to be washed;

means for directing a part of the washing water in spray form upwardlyagainst said lower rack;

means for directing another part of the washing water upwardly in streamform to water dispersing means located generally centrally, and belowsaid upper rack;

said water dispersing means including a rotatable wheel against whichsaid stream of water is directed,

said wheel comprising a center hub having a bottom face from which aportion of said stream is deflected radially,

an outer ring having an inner circumferential surface portion inclinedoutwardly from bottom to top and disposed in the path of said radiallydeflected water to redirect it upwardly, said ring also including anouter circumferential surface portion inclined outwardly in a bottom totop direction to deflect water generally outwardly,

a series of spokes extending between said hub and said ring, and

said hub includes an open segment permitting a portion of said anotherpart of the washing water to pass directly upwardly therethrough.

2. Liquid dispersing apparatus comprising:

means for directing a stream of liquid upwardly against the under sideof a rotatable wheel;

said wheel being supported for rotation about a vertical axis andcomprising a hub, an outer ring, and spokes radiating outwardly fromsaid hub to said ring,

said ring includes an outer circumferential surface portion inclinedoutwardly in an ascending direction to deflect a portion of the risingliquid outwardly,

said ring further includes an inner circumferential surface portioninclined outwardly in an ascending direction to deflect upwardly thatliquid directed radially outwardly from the under side of said hubagainst said inner circumferential surface portion,

said hub includes at least one open segment therein to permit a part ofsaid stream of liquid to pass directly upwardly therethrough.

3. In dishwashing apparatus, water dispersing means for providingselected water distribution patterns in the upper portion of adishwasher, said water dispersing apparatus comprising:

a wheel supported for rotation about a vertical axis in the centralportion of said dishwasher and below the upper portion thereof,

means for directing a stream of water upwardly against the underside ofsaid wheel,

said wheel including a hub, a continuous outer ring, and a series ofspokes extending radially outwardly from said hub to said ring,

said ring inner and outer surfaces being inclined outwardly in anascending direction, and

said hub includes .an open segment therein in the path of a part of saidstream of water to permit a part of said stream of water to passdirectly upwardly therethrough.

4. In a dishwasher according to claim 3:

the under surface of said hub includes substantially flat portions lyingin a horizontal plane above the lower edge of said inner inclinedsurface of said ring so that water deflected outwardly from said undersurface of said hub will be deflected upwardly by said inner surface ofsaid ring.

5. In a dishwasher according to claim 4:

said outer ring inclined surfaces are inclined about 45.

6. In a dishwasher according to claim 3:

said open segment is in the form of an outwardlyopen V.

7. Dishwashing apparatus comprising:

a washing chamber enclosing a lower and an upper openwork dishsupporting rack;

means for supplying water to said chamber;

means for directing a part of said water upwardly in spray form againstsaid lower rack, and directing another part of said water upwardly inthe form of a stream in the central portion of said chamber;

water dispersing means mounted above said stream to receive said streamagainst its lower side and to direct said stream in dispersed formagainst said upper rack,

said dispersing means including a rotatably mounted wheel comprising aninner hub, spokes radiating outwardly through an open annulus, and anouter ring,

said hub including at least one pie-shaped slot therein through which apart of said stream passes directly upwardly, and

said outer ring including an inner circumferential surface portion andan outer circumferential surface portion inclined outwardly in abottom-to-top direction, said outer circumferential surface portionbeing disposed directly in the path of a part of said stream.

References Cited UNITED STATES PATENTS 2,608,983 9/1952 Idle 134-1832,877,778 3/1959 Kirby 134-183 X 3,051,184 8/1962 Gibson 1341833,067,759 12/1962 Gath et al. 134-176 3,144,034 8/1964 Lyman et a1l34176 FOREIGN PATENTS 672,396 2/1939 Germany.

CHARLES A. WILLMUTH, Primary Examiner.

ROBERT L. BLEUTGE, Examiner.

